Now if you are talking about principal shareholders/top mgt. are selling their shares in the offering, normally their holdings are subject to a lock-up of 180 days after ipo. So obviously your friend was referring to number 2 situation. If your friend is a knowledgeable investor and the underwriters of the ipo are financial heavyweights, you may try your luck. If you are not sure about the above, stay away from it. It is your hard-earned money!
Next time follow my advice, such as buying chk three months ago